#7 Water

Scientists believe that when the Earth initially formed, it was
hot and dry, and there was no indoor plumbing.
So where did all the water come from?

The current leading theory is that billions of years ago, water was
brought to Earth along with impacts by comets or icy asteroids.
(Comets are made of rocks and ice.)
Archeological evidence suggests that flushable
toilets were invented much later, around 1500 B.C., on the
island of Crete.

This is pretty amazing, considering that there are 1.37 billion cubic
kilometers of water in the oceans. Luckily, we did not have to pay for
any of it. At current utility rates, and adjusting for inflation, the
water would have cost roughly one third of a million trillion dollars.

Keep this in mind that the next time you're drinking
a tall, refreshing glass of "comet juice".